Injection drug use appears to be increasing in the US. Yet, there are few behavioral interventions to prevent injection drug use initiation and none have been proven to be efficacious in a rigorous, large scale randomized controlled trial (RCT). We propose to address this critical public health need by conducting a large-scale RCT of Change the Cycle (CTC), a single- session, hour-long, one-on-one intervention that aims to reduce injection initiation by encouraging active people who inject drugs (PWID) to not promote drug injection, model injection behavior, describe how to inject, or assist in injection initiations of on-injectors. CTC uses the Information-Motivation-Behavioral skills model (IMB) to illuminate harms of drug injection, increase motivation to not model injection behaviors, and improve behavioral skills to resist request to initiate non-injectors into drug injection. CTC also draws upon social learning theory which posits that people learn behaviors through interaction, observation, behavioral experimentation, and reinforcement. It is highly relevant to the prevention of injection initiation because existing research convincingly demonstrates that active PWID are usually part of an injection-naive person's first injection experience and that active PWID that model or otherwise promote injection drug use contribute to injection drug use initiation. CTC addresses this social process by providing PWID with behavioral skills to resist injection initiation request and behaviors that facilitate the social process of initiation, such as injecting in front of, describing injection to, and speaking positively about injection to non-injectors. CTC pilot study results found significant reductions in injection initiation episodes and some injection initiation social learning risk behaviors; however, the study did not have a control group. Our proposed, large-scale RCT of CTC is the next logical scientific step in identifying a new, low-threshold intervention to prevent of injection initiation. Aim 1: To test the efficacy of CTC on reducing the number of non-injectors initiated into injection by PWID. Aim 2: To test the efficacy of CTC on reducing the number of times PWID are asked to initiate someone into injection. Aim 3: To test whether injection initiation social learning risks (injecting in front of, describing injection to,and speaking positive about injection to non-injectors) act as mediational mechanisms for the efficacy of the CTC intervention on initiation and request to initiate outcomes. To achieve these aims, PWID who report having initiated someone or who have injection-initiation social learning risks in the past year (N=1,076) will be randomly assigned to receive CTC or an equal attention control condition. Injection initiation and injection initiation social learning risks will be collcted at baseline, 6 months, and 12 months. The multidisciplinary team includes the CTC pilot study investigators Drs. Strike and Hunt, and multiple principal investigators Drs. Bluthenthal and Kral, who have recently completed a study on drug injection initiation. If efficacious, CTC could be a much-needed, innovative and practical approach to preventing drug injection initiation.